crt-sony-megatron.slang calls back to crt-sony-megatron-source-pass.slang (as alias SourceSDR) and crt-sony-megatron-hdr-pass.slang (as alias SourceHDR).
You can replace those with instances of stock.slang, but keep the appropriate aliases, and it will load. You would need convert the image into HDR by some other means tho, otherwise the result is extremely washed out.
What exactly are you trying to do here?
I have been tinkering with shader glass in tainted grail fall of Avalon and found the Megatron preset is great in offering an atmosphere that suits this game reminding me of my old crt Panasonic gaming memories. There are areas in the game extremely red that I can’t barely see anything while using the aforementioned settings.
Did you know that there’s a Reshade version of Sony Megatron Colour Video Monitor?
There’s also this:
Post some photos of the screen so we can see.
What settings?
I think I’m ready to have a play around with this. Does anyone want to try before I get a chance?
Where can this gamma cut-off point shader argument be found?
Also what can be done to ensure that the horizontal slots of the slot mask don’t get in the way as they’re not supposed to be affected or visible in this scenario?
That would be the “Inverse Gamma Cutoff (x1000)” setting, at the tail end of the CRT Settings section in the Shader Parameters.
Keep in mind that it’s not going to have nearly as profound an effect as you want it to tho. As MajorPainTheCactus mentioned, a properly set up CRT’s illuminated shadow mask and imperfect blacks aren’t so noticeable in actual use. What you are seeing is a camera artifact, similar to the rolling/hum bars that appear when a CRT is filmed at an unmatched frame rate/shutter speed.
Thank you very much Azurfel.
I’m not looking to create a profound effect actually.
When I use the Base Black Mask feature in CRT-Guest-Advanced, it’s extremwly subtle as is the noise effect in my Mega Bezel and the vast majority of my Mega Bezel Presets. So this is exactly what I would hope to reproduce.
Yeah, I understand what you’re saying but it is there in the case of the former but you’d never pick it up in a Sony Megatron photo unless we set iy up and emulate it. You will see it on CRT photos though.
Update: I’ve tried the full range available in the Shader Parameters for the “Inverse Gamma Cutoff (x1000)” and I can see no change in anything.
Fully updated for crt-guest-advanced-2025-10-12-release1 (rev 3/final), with a decoupled version of the new PAL shader (crt-guest-advanced-pal-decoupled), and new PAL presets made to take advantage of guest.r’s most recent work.
Built on top of:
Image Adjustment (2024.02.07) by hunterk
crt-guest-advanced-2025-10-18-release1 (rev5) by guest.r and Dr. Venom, based in part on Themaister’s NTSC shader
Sony Megatron Colour Video Monitor (2023.10.09) by MajorPainTheCactus
with additional functions based on or inspired by Grade by Dogway
All included “CRT Megatron” presets are currently tuned for the LG C1 and other similar displays (WRGB subpixel layout, with approximately 800 nits Peak Luminance).
The included version of Image Adjustment has been modified to allow for finer control of the effects as i found appropriate.
GPGX MS color fix
Corrects Genesis Plus GX’s Master System color output, which includes minor errors i discovered while implementing the Sega MS Nonlinear Blue Fix.
Sega MS Nonlinear Blue Fix
An implementation of the behavior described in Notes & Measures: Nonlinear Blue on Sega Master System 1 & Other Findings by bfbiii.
This setting automatically adjusts to work with the GPGX MS color fix settings.
Sega MD RGB Palette
An implementation/approximation of the Mega Drive/Genesis RGB palette as discussed here.
Downsample Pseudo Hi-Res
As i understand it, 15KHz CRT displays would treat double-horizontal resolution modes (512x224, 640x240, etc) as tho they were not doubled, resulting in a blending effect, called pseudo hi-res. A number of SFC/SNES games are known to have used this behavior for transparency effects, including Breath of Fire II, Jurassic Park, and Kirby’s Dream Land 3, and as far as i know it is the correct behavior for any device originally meant to be displayed on a 15KHz CRT TV/monitor.
1 = off
2 = Triggers the blending effect whenever the horizontal resolution is more than twice the vertical resolution. This works well with cores that either always output a pseudo hi-res image for compatibility (such as bsnes-jg), or cores that only use pseudo hi-res for pseudo hi-res content (such as SwanStation). True high-resolution/interlaced content is not effected.
3 = Triggers the blending effect whenever the horizontal resolution is 480 or higher. This is needed for cores that display pseudo hi-res content in a true high-resolution container (such as Mesen-S and a number of bsnes variants). Unfortunately, this halves the resolution of true high-resolution/interlaced content, as there is no way to differentiate pseudo hi-res and true high-resolution/interlaced content in these cores.
Internal Resolution
Modified to allow up to 1/16th downsampling. (It’s a surprise tool that will help us later.)
HDR: Content Color Gamut
Out of the box, RetroArch and Megatron clamp colors to the Rec. 709 gamut (Expand Gamut set to Off in RetroAtch, or HDR: Original/Vivid set to Original in Megatron), or stretch that Rec. 709 gamut to an unusual non-standard gamut created by someone at Microsoft (?Chuck Walbourn?) called Expanded 709 (Expand Gamut set to On in RetroArch, or HDR: Original/Vivid set to Vivid in Megatron).
Obviously, this is undesirable, as all of the major “retro” color gamuts include colors that fall outside of Rec. 709.
Serendipitously, i found that it was possible to turn this problem into it’s own solution by simply adding additional color gamuts to the “HDR: Original/Vivid”, renaming it “HDR: Content Color Gamut” to better reflect it’s newfound purpose.
When using this setting, Colour System should be set to 0/r709, and Phosphors should be set to 0/NONE.
Options are as follows:
Gamut Overshoot Fix
A fix MajorPainTheCactus came up with to deal with the color errors i noticed using lilium’s HDR analysis shader. (Sony Megatron Colour Video Monitor)
He decided not to implement it at the time, as he didn’t think it wouldn’t make a perceptible difference, but a friend and i both came to the conclusion that it makes certain test pattern colors look more like they do with no shaders applied, so i have continued to use it. There should be no downside. (Sony Megatron Colour Video Monitor)
Scanline Multiplier/Divisor
Multiplies or divides the number of scanlines.
Useful for cases like DOS games meant for 31KHz displays, which output 320x200 that was then double scanned to 640x400.
The divisor options are handy for displaying increased internal resolution output from 3D cores that don’t include a good downsample option, such as PPSSPP. I strongly recommend using this setting in conjuction with crt-guest-advanced-ntsc’s Internal Resolution setting to reduce shimmering.
Built on top of:
Image Adjustment (2024.02.07) by hunterk
crt-guest-advanced-2025-10-22-release1 (rev2) by guest.r and Dr. Venom, based in part on Themaister’s NTSC shader
Sony Megatron Colour Video Monitor (2023.10.09) by MajorPainTheCactus
with additional functions based on or inspired by Grade by Dogway
All included “CRT Megatron” presets are currently tuned for the LG C1 and other similar displays (WRGB subpixel layout, with approximately 800 nits Peak Luminance).
The included version of Image Adjustment has been modified to allow for finer control of the effects as i found appropriate.
GPGX MS color fix
Corrects Genesis Plus GX’s Master System color output, which includes minor errors i discovered while implementing the Sega MS Nonlinear Blue Fix.
Sega MS Nonlinear Blue Fix
An implementation of the behavior described in Notes & Measures: Nonlinear Blue on Sega Master System 1 & Other Findings by bfbiii.
This setting automatically adjusts to work with the GPGX MS color fix settings.
Sega MD RGB Palette
An implementation/approximation of the Mega Drive/Genesis RGB palette as discussed here.
Downsample Pseudo Hi-Res
As i understand it, 15KHz CRT displays would treat double-horizontal resolution modes (512x224, 640x240, etc) as tho they were not doubled, resulting in a blending effect, called pseudo hi-res. A number of SFC/SNES games are known to have used this behavior for transparency effects, including Breath of Fire II, Jurassic Park, and Kirby’s Dream Land 3, and as far as i know it is the correct behavior for any device originally meant to be displayed on a 15KHz CRT TV/monitor.
1 = off
2 = Triggers the blending effect whenever the horizontal resolution is more than twice the vertical resolution. This works well with cores that either always output a pseudo hi-res image for compatibility (such as bsnes-jg), or cores that only use pseudo hi-res for pseudo hi-res content (such as SwanStation). True high-resolution/interlaced content is not effected.
3 = Triggers the blending effect whenever the horizontal resolution is 480 or higher. This is needed for cores that display pseudo hi-res content in a true high-resolution container (such as Mesen-S and a number of bsnes variants). Unfortunately, this halves the resolution of true high-resolution/interlaced content, as there is no way to differentiate pseudo hi-res and true high-resolution/interlaced content in these cores.
Internal Resolution
Modified to allow up to 1/16th downsampling. (It’s a surprise tool that will help us later.)
HDR: Content Color Gamut
Out of the box, RetroArch and Megatron clamp colors to the Rec. 709 gamut (Expand Gamut set to Off in RetroAtch, or HDR: Original/Vivid set to Original in Megatron), or stretch that Rec. 709 gamut to an unusual non-standard gamut created by someone at Microsoft (?Chuck Walbourn?) called Expanded 709 (Expand Gamut set to On in RetroArch, or HDR: Original/Vivid set to Vivid in Megatron).
Obviously, this is undesirable, as all of the major “retro” color gamuts include colors that fall outside of Rec. 709.
Serendipitously, i found that it was possible to turn this problem into it’s own solution by simply adding additional color gamuts to the “HDR: Original/Vivid”, renaming it “HDR: Content Color Gamut” to better reflect it’s newfound purpose.
When using this setting, Colour System should be set to 0/r709, and Phosphors should be set to 0/NONE.
Options are as follows:
Gamut Overshoot Fix
A fix MajorPainTheCactus came up with to deal with the color errors i noticed using lilium’s HDR analysis shader. (Sony Megatron Colour Video Monitor)
He decided not to implement it at the time, as he didn’t think it wouldn’t make a perceptible difference, but a friend and i both came to the conclusion that it makes certain test pattern colors look more like they do with no shaders applied, so i have continued to use it. There should be no downside. (Sony Megatron Colour Video Monitor)
Scanline Multiplier/Divisor
Multiplies or divides the number of scanlines.
Useful for cases like DOS games meant for 31KHz displays, which output 320x200 that was then double scanned to 640x400.
The divisor options are handy for displaying increased internal resolution output from 3D cores that don’t include a good downsample option, such as PPSSPP. I strongly recommend using this setting in conjuction with crt-guest-advanced-ntsc’s Internal Resolution setting to reduce shimmering.
In Reshade 6.6.1:
13:01:32:698 [16368] | ERROR | Failed to compile ‘C:\Users\awright\Documents\Fightcade\emulator\fbneo\reshade-shaders\Shaders\SonyMegatron.fx’: C:\Users\awright\Documents\Fightcade\emulator\fbneo\Shader@0x000002644F24DC00(277,16-53): warning X3571: pow(f, e) will not work for negative f, use abs(f) or conditionally handle negative values if you expect them C:\Users\awright\Documents\Fightcade\emulator\fbneo\Shader@0x000002644F24DC00(282,20-29): error X3504: array index out of bounds
Built on top of:
Image Adjustment (2024.02.07) by hunterk
crt-guest-advanced-2025-10-27-release1 by guest.r and Dr. Venom, based in part on Themaister’s NTSC shader
Sony Megatron Colour Video Monitor (2023.10.09) by MajorPainTheCactus
with additional functions based on or inspired by Grade by Dogway
All included “CRT Megatron” presets are currently tuned for the LG C1 and other similar displays (WRGB subpixel layout, with approximately 800 nits Peak Luminance).
The included version of Image Adjustment has been modified to allow for finer control of the effects as i found appropriate.
GPGX MS color fix
Corrects Genesis Plus GX’s Master System color output, which includes minor errors i discovered while implementing the Sega MS Nonlinear Blue Fix.
Sega MS Nonlinear Blue Fix
An implementation of the behavior described in Notes & Measures: Nonlinear Blue on Sega Master System 1 & Other Findings by bfbiii.
This setting automatically adjusts to work with the GPGX MS color fix settings.
Sega MD RGB Palette
An implementation/approximation of the Mega Drive/Genesis RGB palette as discussed here.
Downsample Pseudo Hi-Res
As i understand it, 15KHz CRT displays would treat double-horizontal resolution modes (512x224, 640x240, etc) as tho they were not doubled, resulting in a blending effect, called pseudo hi-res. A number of SFC/SNES games are known to have used this behavior for transparency effects, including Breath of Fire II, Jurassic Park, and Kirby’s Dream Land 3, and as far as i know it is the correct behavior for any device originally meant to be displayed on a 15KHz CRT TV/monitor.
1 = off
2 = Triggers the blending effect whenever the horizontal resolution is more than twice the vertical resolution. This works well with cores that either always output a pseudo hi-res image for compatibility (such as bsnes-jg), or cores that only use pseudo hi-res for pseudo hi-res content (such as SwanStation). True high-resolution/interlaced content is not effected.
3 = Triggers the blending effect whenever the horizontal resolution is 480 or higher. This is needed for cores that display pseudo hi-res content in a true high-resolution container (such as Mesen-S and a number of bsnes variants). Unfortunately, this halves the resolution of true high-resolution/interlaced content, as there is no way to differentiate pseudo hi-res and true high-resolution/interlaced content in these cores.
Internal Resolution
Modified to allow up to 1/16th downsampling. (It’s a surprise tool that will help us later.)
HDR: Content Color Gamut
Out of the box, RetroArch and Megatron clamp colors to the Rec. 709 gamut (Expand Gamut set to Off in RetroAtch, or HDR: Original/Vivid set to Original in Megatron), or stretch that Rec. 709 gamut to an unusual non-standard gamut created by someone at Microsoft (?Chuck Walbourn?) called Expanded 709 (Expand Gamut set to On in RetroArch, or HDR: Original/Vivid set to Vivid in Megatron).
Obviously, this is undesirable, as all of the major “retro” color gamuts include colors that fall outside of Rec. 709.
Serendipitously, i found that it was possible to turn this problem into it’s own solution by simply adding additional color gamuts to the “HDR: Original/Vivid”, renaming it “HDR: Content Color Gamut” to better reflect it’s newfound purpose.
When using this setting, Colour System should be set to 0/r709, and Phosphors should be set to 0/NONE.
Options are as follows:
Gamut Overshoot Fix
A fix MajorPainTheCactus came up with to deal with the color errors i noticed using lilium’s HDR analysis shader. (Sony Megatron Colour Video Monitor)
He decided not to implement it at the time, as he didn’t think it wouldn’t make a perceptible difference, but a friend and i both came to the conclusion that it makes certain test pattern colors look more like they do with no shaders applied, so i have continued to use it. There should be no downside. (Sony Megatron Colour Video Monitor)
Scanline Multiplier/Divisor
Multiplies or divides the number of scanlines.
Useful for cases like DOS games meant for 31KHz displays, which output 320x200 that was then double scanned to 640x400.
The divisor options are handy for displaying increased internal resolution output from 3D cores that don’t include a good downsample option, such as PPSSPP. I strongly recommend using this setting in conjuction with crt-guest-advanced-ntsc’s Internal Resolution setting to reduce shimmering.
Hey man, thanks a lot for your continued support and dedication to our beloved shader tools!
I’ve tested it and was able to eventually tweak things to my liking after some experimentation. Although I’m strongly intertwined and invested in the shader stack I currently use, I’m not ruling out a switch over to your cleaner and more accurate stack at some point in the future.
Nonetheless, you’ve taken the, (abandoned?), no offense to @MajorPainTheCactus Sony Megatron Colour Video Monitor shader and kept it in line with current trends and developments which is quite commendable and appreciated and something that others might eventually live and grow to appreciate.
I think this shader “suffers” from being a bit “ahead of its time” for the average user and it also has a bit of a marketing / PR issue since its difficult to showcase on current setups to mainstream audiences.
Those who know, know though but that is a niche of a niche.
So I would like to nominate AzMods20251108 for a RetroArch PR to reside alongside the existing Sony Megatron Colour Video Monitor shader which can remain as a simpler, leaner foundational vanilla version.
I propose that you take a look at the stack I currently use in my miniLED Epic preset pack and include and incorporate some of the additional features which may lie therein, for example additional RGB Masks which replaced some of the “8K” Masks and Optional presets which incorporate XBR-LEVEL-2.
The IMG_MOD_CYBERLAB Grain feature can be excised in favour of the new RF Noise feature from decoupled CRT-Guest-Advanced-NTSC.
That’s about it basically.
Again, thanks a lot to you, @guest.r, @Dogway, @HunterK, @MajorPaintheCactus and all others who helped make this shader what it is today.
I’ve been thinking it might be time for a separate “AzMods” topic myself, since this thread has gotten pretty quiet lately. I’ll probably consider if i want to stick with the AzMods name or go with something else, and then post that some time in the next couple weeks, with a few new additions i have been considering.
I will take a look and see what i might be able to include!
In hindsight, I’m almost certain that those were the white subpixels alone.
I’ve been loving the original presets for Megatron, especially now I’ve got Retroarch working in HDR on my LG BX.
I’ve been working on getting them going in Reshade on my Bazzite mini-PC build; and I’m having mixed results.
I’m interested to know what settings @MajorPainTheCactus uses in his show case video on Youtube with Dead Cells; and I’m also interested in a discussion about the best way to setup the CRT_HEIGHT resolution in order to get a decent CRT emulation whilst still making text in modern games more readable.
I got into this hole with Octopath Traveller, and I am finding with that it needs a close-to-native CRT_Height resolution and a high TVL to make the high resolution text in the game readable. I’ve gone with the JVC shadowmask preset on that game with the resolution settings matching the game; and whilst the effect is subtle it is worth it.
Another game on Steam which really benefits from a shader is Jack Move; and it looks great.
I was using the Guest Reshade port previously but its GPU overhead is considerable in comparison to Megatron, and on miniPCs you need all the power you can get!
Thanks again for all your work on this guys. /essay
Hi all, if anyone’s using a Radeon 6000 series on Windows, please check Megatron using aperture mask with the vulkan video driver. Any issues? On my machine, instead of a mask I’m getting a solid colour, sometimes red, sometimes green. If I remove the amd drivers the mask is fine, but obviously my gpu performance drops considerably until I reinstall the drivers. It’s only the vulkan or opengl video drivers in RA experiencing this, directx is fine
@Wilch1 What display are you using? What’s it’s native resolution and subpixel layout?
What desktop resolution are you using? What preset or Shader Parameters have you tried?
Did you set the Display’s Subpixel Layout to match your Display’s subpixel layout?
Post some screenshots and / or photos of the screen so that others can see what you’re trying to describe.
Have you tried rolling back or updating your GPU Drivers to the latest version, including Beta versions?
Are you sure your colour format is set to RGB 4:4:4 Full for no chroma subsampling?
I registered just to comment on this issue. I have 6900xt and same problem, when I use aperture mask whole screen is red color only. Other masks works normal, only aperture grill is not working properly. For me problem started when Windows 11 was updated to version 24h2 and it is broken ever since then, before that it was working fine. I also have win10 partition and it is fine there also.
